Traitorous

Part of speech: adjective (a.)

1. Guilty of treason; treacherous; perfidious; faithless; as, a traitorous officer or subject. Shak.

2. Consisting in treason; partaking of treason; implying breach of allegiance; as, a traitorous scheme. -- Trai"tor*ous*ly, adv. -- Trai"tor*ous*ness, n.